One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6)(7,11)(8,9)(10,12)(13,14,17,18)(15,19,23,22)(16,24,26,20)(21,28,25,27)(1,2)(3,4)(6,9)(10,11)(13,15,17,23)(14,19,18,22)(16,25,26,21)(20,28,24,27)(2,4)(13,16)(14,20)(15,21)(17,26)(18,24)(19,27)(22,28)(23,25) involution — undirected(2,4)(14,18)(15,22)(19,23)(20,24)(21,28)(25,27) involution — undirected(5,7,8,12)(6,10,9,11)(15,23)(16,26)(19,22)(20,24)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.